To compare the perioperative, functional, and oncologic outcomes between nerve sparing and lateral prostate capsule sparing robot-assisted radical cystectomy with orthotopic ileal neobladder in male patients with bladder cancer.

This study will enroll male patients with bladder cancer who will undergo robot-assisted radical cystectomy with orthotopic ileal neobladder. The patients will be distributed into two comparable groups according to surgical procedures: nerve sparing group and lateral prostate capsule sparing group. Patient demographics and pathologic, perioperative, functional, and oncologic outcomes will be compared between the two groups.

Inclusion Criteria:

1. Male patients aged 18 or older.
2. Patients those who are diagnosed with urothelial carcinoma.
3. Patients those who are without tumour in the bladder neck or urethra, and prostate cancer was ruled out by MRI and serum T-PSA<2.5ng/ml.
4. Patients those who are capable of receiving radical cystectomy with orthotopic ileal neobladder.
5. Patients those who are able to cooperate and complete the follow-up.
6. Patients those who volunteer to participate in this study and sign the informed consens.

Exclusion Criteria:

1. Patients thsoe who are diagnosed distant metastasis before surgery.
2. Patients those who are diagnosed with other malignancies.
3. Patients those who had received pelvic radiotherapy or major pelvic operation.